Cold Aura.
The ice toad radiates cold in a 10 foot radius from it's body. Any target within this radius at the start of their turn will take 3d6 cold damage. A successful Constitution saving throw means the target takes half damage.

Swallow. The ice toad makes one bite attack against a Medium or smaller target it is grappling. If the attack hits, the target is swallowed, and the grapple ends. The swallowed target is blinded and restrained, it has total cover against attacks amd other effects outside the ice toad, and it takes 10 (3d6) acid damage at the start of each of the ice toad's turns. The ice toad can have only one target swallowed at a time.
If the ice toad dies, a swallowed creature is no longer restrained by it and can escape from the corpse using 5 feet of movement, exiting prone.
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